Oh I remember reading that part, sure.... But you're interpreting Scourge's visions just like he was.... that they were absolutely certain. Revan told him, just like Yoda to Luke "Always in motion, the future is." There was no absolute way of knowing if Scourge was seeing the absolute future. He felt that he knew all possible outcomes, I don't think that a dark sider would be THAT attuned to the force. Even Scourge commented (on some page in the book I don't remember) that there was no use for dark side prophets, because most dark siders were consumed by their anger, hatred, etc. I just think Scourge was having a brush with BOTH sides of the force, saw the potential for its use, and then like all true dark siders, felt.... "hey, I instantly got this future vision thing down!"